Antenna tuners can be used to extend the battery life and/or quality of service under adverse conditions by correcting for mismatches at the antenna. Modern cellular telephone handsets are optimized to provide long battery life while in standby mode. Typically, the handset does not transmit in standby mode.
Without bias applied, the impedance point generated by a prior art antenna tuner is not generally near the impedance expected by the transmit/receive circuitry in the handset. This detunes these circuits and results lower quality of service for the handset. Another undesirable option is to continually bias the antenna tuner at the expense of decreased battery life. Thus, there is a strong need for an antenna tuner topology that has minimal impact on performance of the handset in a passive state and would extend handset battery life by not needing its bias voltages generated to provide acceptable service in standby mode.